Development of a flow-cytometry-based method to measure the expression of cell surface molecules on endothelial cells is proposed for screening for novel regulators of inflammation. Many anti-inflammatory drugs, including corticosteroids, cyclooxygenase inhibitors and lipoxygenase inhibitors, inhibit the cytokine-dependent expression of certain endothelial cell surface molecules in culture. Our preliminary studies indicate that drugs can be distinguished based on their selective effects on particular cell surface molecules and/or under particular activation conditions. A robust assay system that can rapidly measure these effects under conditions that are more relevant to complex disease processes may be a useful tool for the rapid identification and characterization of novel anti-inflammatory drug compounds. The development of a multi-parameter flow cytometry method that allows the simultaneous measurement of multiple cell surface molecules in such a system may provide an innovative strategy for identifying and characterizing novel regulators of inflammation from synthetic or natural product libraries. PROPOSED COMMERCIAL APPLICATION: Commercial application: identifying anti-inflammatory drug compounds for pharmaceutical drug discovery.